Patent · US Expired

Light emitting diode structures

US7509012B2 · kind B2 · utility

8Cited by
4References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 22, 2004
Grant dateMar 24, 2009
Priority date
Expiry dateSep 22, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10H20/872
  • WIPO fieldMicro-structural and nano-technology
  • WIPO sectorChemistry

Abstract

According to one aspect of the present invention, a light emitting diode (LED) structure including an active core layer and at least one substrate layer having a first refractive index, comprises a 2-dimensional photonic quasicrystal in the structure, the photonic quasicrystal comprising an array of regions having a second refractive index, the array exhibiting long range order but short range disorder. The long range order is associated with diffractive properties of the structure and gives rise to uniform-far field diffraction patterns from the LED. The present invention enjoys the benefit of improved light extraction from LEDs without undesirable far field illumination patterns.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.